<?php
class Person
{
    private $name;
    
    function __construct($name)
    {
        $this->name = $name;
    }
    
    function __toString()
    {
        return $this->name;
    }
}

$obj = new Person("小明");
print $obj;
?>

<?php
class NullHandleException extends Exception
{
    function __construct($message)
    {
        parent::__construct($message);
    }
}
    
function printObject($obj)
{
    if($obj == NULL) {
        throw new NullHandleException("printObject received NULL object");
    }
    print $obj . "<br />";
}

class MyName
{
    function __construct($name)
    {
        $this->name = $name;
    }
    
    function __toString()
    {
        return $this->name;
    }
    private $name;
}
    
try {
    printObject(new MyName("Bill"));
    printObject(NULL);
    printObject(new MyName("jane"));
} catch (NullHandleException $exception) {
    print $exception->getMessage();
    print " in file " . $exception->getFile();
    print " on line " . $exception->getLine() . "<br />";
} catch (Exception $exception) {
    //这里将不会被执行
}

?>